Now, first off, there's no such thing.
But, let's imagine that we live in the same dimension as Buffy (most of the guys and a few of the women start paying attention), or the Anne Rice novels, Blade, whatever.
Vampires are real. God is distant and removed. There is an epic, but drawn out and irresolvable struggle between good and evil. You get accosted by a vampire in an alley, and, for some reason, they decide that you'd make a better recruit than meal.
So, given a choice between being dinner, and becoming a vampire (standard pros and cons; very strong, getting stronger over time, almost unkillable, unless someone has a pencil or holy water, continued existence unless killed, funny sleeping habits and not very good reaction to direct sunlight), what would you choose?
Anne Rice nicely explores the dillema in 'Interview with a Vampire'. You have Lestat, very cool, whose attitude it "humans are cattle, let's party". And it's a bloody good point - if you were four hundred years old say, humans would appear so transitory that one's moral qualms over feeding from them would be equivalent to thier qualms eating lamb. Or you have Louis, who is a whinning little whimp, and can't see what an opportunity he has.
Your eventual fate is ceasing to exist; I'd prefer pert teenage girls to Van Helsing or forgeting the SPF100 anyday. But until then, well... oh, and you could 'take' whoever you wanted with you, friends, family, lovers.
So, dinner, or 'demon'? What would you do?
Personally speaking, me and my girlfriend have decided that Spike and Drew are raw amateurs, and that we'd be far more stylishly nasty than them.